What is ecumenism?
Question 09071
Ecumenism is the movement toward greater unity and cooperation among Christian churches and denominations. It has taken many forms over the past century, from informal local partnerships to vast institutional structures like the World Council of Churches. For evangelical Christians, the question is not whether unity matters, because Jesus Himself prayed for it (John 17:20-23), but what kind of unity Scripture requires and where the boundaries of legitimate cooperation lie.
The Biblical Call to Unity
The New Testament places a high value on Christian unity. Jesus’ prayer in John 17:21, “that they may all be one, just as you, Father, are in me, and I in you, that they also may be in us, so that the world may believe that you have sent me,” is one of the most compelling statements in all of Scripture. Paul’s appeal in Ephesians 4:3 to be “eager to maintain the unity of the Spirit in the bond of peace” reinforces the point. There is “one body and one Spirit” (Ephesians 4:4), and the divisions that fracture the visible church are a genuine scandal that weakens the church’s witness and grieves the God who called it into being.
This biblical call to unity is real and must not be dismissed as impractical idealism. The early church’s koinonia (Acts 2:42-47) was not a vague aspiration but a lived reality, and every generation of believers should feel the weight of Jesus’ prayer and the distance between it and the fractured state of the visible church today.
Where Ecumenism Goes Wrong
The difficulty arises when the desire for unity is pursued at the expense of truth. Paul’s instruction in Ephesians 4:3 to maintain unity is inseparable from his insistence in the same chapter that the church must grow up into “the unity of the faith and of the knowledge of the Son of God” (Ephesians 4:13) and must no longer be “tossed to and fro by every wind of doctrine” (Ephesians 4:14). Unity that ignores or minimises doctrinal truth is not the unity Scripture envisions. It is a counterfeit that replaces the substance of the faith with organisational cooperation.
The modern ecumenical movement, particularly as represented by the World Council of Churches (founded 1948), has repeatedly subordinated doctrinal clarity to institutional unity. Organisations that include both evangelical and liberal Protestant churches, Orthodox churches, and in some contexts Roman Catholic observers inevitably find that the doctrinal common ground shrinks to the point of meaninglessness. When the authority of Scripture, the exclusivity of Christ for salvation, and the nature of the gospel itself are treated as matters on which sincere Christians may disagree, the resulting “unity” is built on a foundation of deliberate ambiguity rather than shared conviction.
Ecumenical engagement with Roman Catholicism raises particular concerns. The fundamental soteriological differences between evangelical Protestantism and Roman Catholic teaching are not secondary disagreements about church practice or eschatological timetables. They concern how a person is saved. Roman Catholic theology teaches that justification is a process involving faith, baptism, the sacraments, and ongoing cooperation with grace, culminating in purgatorial purification for most believers. Evangelical theology, grounded in Romans 3:28 and Ephesians 2:8-9, teaches that justification is by grace alone through faith alone in Christ alone, received in a moment and complete at the point of belief. These are not compatible positions that can be papered over with carefully worded joint declarations. The 1994 document “Evangelicals and Catholics Together” attempted precisely this and was rightly criticised by many evangelical leaders for obscuring the very heart of the gospel.
What Legitimate Unity Looks Like
Genuine Christian unity is built on a shared commitment to the gospel, the authority of Scripture, and the essential doctrines of the faith: the Trinity, the full deity and humanity of Christ, the bodily resurrection, salvation by grace through faith, and the sufficiency of Scripture. Where these are held in common, believers can and should cooperate, even where secondary differences remain. An evangelical Baptist and a Bible-believing Presbyterian may disagree about baptism, eschatology, and church government, yet stand on the same gospel foundation and serve the same Lord with the same confidence in the same Scriptures. That is a basis for genuine partnership.
Where the gospel itself is in dispute, or where the authority of Scripture is not affirmed, organisational unity becomes a liability rather than a witness. Paul’s instruction in 2 Corinthians 6:14, “Do not be unequally yoked with unbelievers,” has application beyond marriage. Formal partnerships that require evangelicals to treat as fellow believers those who deny the sufficiency of Christ’s work or the authority of Scripture compromise the very gospel they are called to proclaim.
So, now what?
Ecumenism in its broadest institutional form has consistently sacrificed doctrinal integrity for the appearance of unity, and evangelicals are right to approach it with caution. This does not mean retreating into isolation. It means pursuing the kind of unity Jesus prayed for: unity in truth, grounded in the gospel, expressed in genuine love and cooperation among those who share the faith once delivered to the saints (Jude 3). Where that common faith exists, the barriers between denominations and traditions should be as low as possible. Where it does not, pretending otherwise does not honour Christ; it dishonours the gospel He died to establish.
“I appeal to you, brothers, by the name of our Lord Jesus Christ, that all of you agree, and that there be no divisions among you, but that you be united in the same mind and the same judgement.” 1 Corinthians 1:10